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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Ecological, morphological, genetic, and life history comparison of two sockeye salmon populations, Tustumena Lake, Alaska /

Woody, Carol Ann. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [90]-107).
82

Life history divergence and population structure of New Zealand chinook salmon : a study of contemporary microevolution /

Kinnison, M. T. January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 124-141).
83

Dynamics of planktonic larval sea louse distribution in relation to Atlantic salmon (Salmo salar L.) farms in a Scottish sea loch

Penston, Michael. January 2009 (has links)
Thesis (Ph.D.)--Aberdeen University, 2009. / Title from web page (viewed on June 26, 2009). With: Spatial and temporal distribution of Lepeophtheirus salmonis (Krøyer) larvae in a sea loch containing Atlantic salmon, Salmo salra L., farms on the north-west coast of Scotland / M. J. Penston ... et al. Journal of fish diseases. 2008: 31, 361-371. With: Reduced Lepeophtheirus salmonis larval abundance in a sea loch on the west coast of Scotland between 2002 and 2006 / Michael J. Penston, Colin P. Millar, Ian Davies. Dis. Aquat. Org. 2008: 81, 109-117. Includes bibliographical references.
84

Maternal effects and phenotypic mismatch in hatchery-reared Atlantic salmon

Stringwell, Rebecca January 2015 (has links)
Phenotypic variation was previously thought to be the result of complex interactions between an individual's genotype and the environment in which it exists. It is, however, now evident that an individual's phenotype may also be shaped by the environmental variation experienced by the mother, i.e. maternal effects. Environmental maternal effects have the potential to generate rapid phenotypic change in a population and so may be particularly important for evolution at ecological time-scales. The general aim of this thesis was to examine how maternal effects may influence offspring fitness and life history traits in Atlantic salmon (Salmo salar L.1758). For this species, the early juvenile period is the most critical due to their complex life cycle. Offspring rely on maternal provisioning during the early stages of development for growth and survival. Several studies on Atlantic salmon have emphasised the benefits of developing from larger eggs, yet it is unclear how the effects of rearing environment influence early life development. The thesis therefore investigated the effects of variation in maternal provisioning and female rearing environment on the development and physiology of embryos, the behaviour of newly emerged fry and the survival of fry released into the wild. Also assessed were the phenotypic changes among juvenile salmon released into the wild compared to those retained in the hatchery. For this maternal provisioning was manipulated by varying the length of time mothers from the same genetic background were maintained in captivity (2 months, 14 months and 26 months). The results of this thesis demonstrate that both maternal provisioning and female rearing environment alter the development and behaviour of salmon fry, opercular beat rate (a proxy for metabolic rate) and yolk sac absorption, and ultimately survival in the wild. Hatchery-reared fry were found to be maladapted to the natural environment for a number of phenotypic traits which are known to impact survival and the longer fry are retained in the hatchery prior to release the more phenotypically mismatched to the natural environment they become. However, increased egg size brought about my retaining females in captivity improved survival.
85

A demand analysis of processed salmon from the West Coast

Wood, William Robert 04 September 1969 (has links)
The primary purpose of the study was to identify the demand for processed salmon from the West Coast. The basic approach in the demand analysis was to identify those variables that determine the supply and demand for processed salmon. An econometric model was established containing the supply and demand equations from which estimates for the parameters in each equation were obtained. The main source of data for salmon was obtained from publications printed by the Bureau of Commercial Fisheries, and the Pacific Fisherman. Ordinary least squares using the wholesale price as the dependent variable in the demand equation was the principal method of analysis. Coefficients for the demand expressed flexibilities with respect to the price. Price flexibilities calculated at the mean values for all processed salmon indicated that a ten percent increase in volume would reduce price by a lesser percentage. For increases in the supply of processed salmon, total revenues would increase, where decreases in supply would cause total revenues to decline. The results of the study also indicated that for a small percentage increase in disposable income, prices would increase but by a lesser percentage. Inverse relationships were noted between the price of salmon and the quantity of canned meat and meat products. Effects of population changes on the price of processed salmon were inconclusive. / Graduation date: 1970
86

Ecological influence of bacterial kidney disease on juvenile spring chinook salmon : effects on predator avoidance ability, smoltification, and physiological responses to stress

Mesa, Matthew G. 28 January 1999 (has links)
Juvenile chinook salmon (Oncorhynchus tshawytscha) were experimentally infected with Renibacterium salmoninarum (Rs), the causative agent of bacterial kidney disease (BKD), to investigate the effects of BKD on three aspects of juvenile salmonid performance: (1) predator avoidance ability; (2) smoltification; and (3) physiological responses to stress. For these experiments, fish with different Rs-infection profiles (created by using an immersion challenge method) were sampled to assess physiological change and subjected to various performance tests during disease progression. When equal numbers of Rs-challenged and unchallenged fish were subjected to predation by northern pikeminnow (Ptychocheilus oregonensis) or smallmouth bass (Micropterus dolomieui), Rs-challenged fish were eaten in significantly greater numbers than controls by nearly two to one. A progressively worsening infection with Rs did not alter the normal changes in gill ATPase and condition factor associated with smoltification in juvenile chinook salmon. A dramatic proliferation of BKD was associated with maximal responses of indicators of smoltification, suggesting that the process of smoltification itself can trigger outbreaks of disease. When Rs-infected fish were subjected to three 60-s bouts of severe handling that were separated by 48-72 h, this experience did not lead to higher infection levels or increased mortality when compared to diseased fish that did not receive the stressors. Furthermore, the kinetics of plasma cortisol, glucose, and lactate over 24-h following each stressor were similar between fish with moderate to high BKD and those that had low or no detectable infection. Fish with moderate to high Rs infections had higher titers of cortisol and lactate prior to each application of the stressor and were also unable to consistently elicit a significant hyperglycemia in response to the stressors when compared to fish with low infection levels. During all experiments, fish consistently developed decreased hematocrits and blood glucose levels and increased levels of cortisol and lactate as the disease worsened, indicating that BKD is stressful, particularly during the later stages. Collectively, these results illustrate the impact of BKD on juvenile salmonids and have also ascribed some ecological significance to this disease beyond that of direct pathogen-related mortality. / Graduation date: 1999
87

The Pacific Coho salmon fishery : an intraseasonal and interregional economic analysis of the ex-vessel market

Swartz, A. Nelson 17 November 1978 (has links)
The ex-vessel coho salmon market has been paid scant attention in the study of the salmon resources. This study is an attempt to advance an understanding of the variations of ex-vessel prices and landings during the coho season as well as between the various coastal ports where the fish is landed. This study presents an empirical analysis of the ex-vessel port markets for coho salmon in Oregon and Washington. The objectives of the study are to investigate the variation in landings and prices during the fishing season and to compare those differences between ports for both states. This study focuses on the determination of the ex-vessel price mechanism and the decision behavior of coho fishermen in their choice of ports to land the catch. An economic model of each port is developed to explain the buying behavior of processors and the selling behavior of fishermen. Each port is treated as a distinctive market subject to external changes in the abundance of coho, the conditions of the wholesale markets, and the responsiveness of fishermen to prices in other ports. Several econometric models are constructed to determine the distinctive characteristics of the Oregon and Washington ex-vessel port markets. The demand and supply at the different ports are estimated by applying regression analysis to 32 different sets of data. These data include a single year (1976) of transaction records for the twelve Oregon ports, and four years (1973-1976) of landings records for the five Washington coastal ports. Three different models are used; a simultaneous equations model, a recursive model, and a single equation model. The major findings in the study are as follows: the ex-vessel demand in most Oregon or Washington ports is highly elastic, which suggests that changes in seasonal landings at a port do not have any significant impact on the ex-vessel price. While fishermen and other industry observers have noted differences in seasonal ex-vessel price between ports, such differences do not appear to exist. Average seasonal price differences between ports do not vary when appropriate weights are applied to the average price calculations. The size (in pounds) of the coho salmon plays a major role in the determination of the intraseasonal ex-vessel demand at all ports. Estimations performed without accounting for this variation fail to adequately explain ex-vessel price variation. Another variable found to be a key factor in the explanation of ex-vessel prices is the wholesale price. This factor and the size variable accounted for most of the variation in ex-vessel port prices. Even though the seasonal prices between ports are similar, the intraseasonal variation in port price is partly the result of competition for the fisherman's catch of coho. When two ports are located in such a way that fishermen may easily land at either one, fishermen appear to land at the port where price is greater. Ports such as La Push and Neah Bay in Washington, and Bandon and Winchester Bay in Oregon are the ports found to be alternative ports for the fishermen catching coho in those areas. Coastal ex-vessel prices do not appear to be established as a result of equilibrium conditions at any particular port. Rather, ex-vessel price and market clearing quantities are determined in the aggregate. Each port's buyers will establish port price based on the current aggregate equilibrium condition. The aggregate coastal demand for coho at the ex-vessel level was estimated for the 1976 season and found to be highly price elastic. Given that aggregate supplies are augmentable, increases in coastal landings will increase total returns to the ex-vessel fishery. One additional finding suggests that the number of buyers in most ports does not play a significant role in the determination of intraseasonal variation of port ex-vessel prices. / Graduation date: 1979
88

Cardiorespiratory modifications, and limitations, in growth hormone transgenic Atlantic salmon (Salmo salar) /

Deitch, Eric, January 2005 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2005. / Bibliography: leaves 80-94.
89

Inbreeding and its consequences for genetic variation and early life history in chinook salmon /

Wang, Shizhen, January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 108-138).
90

Endocrine growth regulation in salmon : mechanisms of nutritional control of the growth axis /

Pierce, Andrew L. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 126-151).

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